The present invention relates to a laryngeal mask airway device. More specifically, the present invention relates to a laryngeal mask airway device having a tab disposed near the device's proximal end for facilitating position control of the device.
The laryngeal mask airway device is a well known device that is useful for establishing airways in unconscious patients. One popular laryngeal mask airway device has been marketed commercially for many yeas as the “Classic” by the Laryngeal Mask Company of Cyprus. Such devices are described for example in U.S. Pat. No. 4,509,514. The Classic is a reusable device and is guaranteed to survive at least forty sterilizations, and in practice these devices may generally be sterilized (and reused) more than forty times before becoming too worn for reuse. In recent years, attempts have been made to develop reduced cost, disposable, laryngeal mask airway devices. U.S. patent application Ser. Nos. 09/544,681 and 10/138,806, which name the inventor of the present application, describe several embodiments of disposable laryngeal mask airway devices.
FIGS. 1A, 1B, and 1C show various views of a prior art disposable laryngeal mask airway device 100 when the cuff is inflated. FIG. 2 shows a partially sectional side view of device 100 when inserted into a patient. Referring to FIG. 1A, device 100 includes an airway tube 110 and a mask portion 130. Mask portion 130 includes a flat plate 132 and an inflatable cuff 134. Mask portion 130 extends from a proximal end 136 to a distal end 138. Mask portion 130 is attached to a distal portion 112 of airway tube 110. Device 100 also includes an inflation line 190 (shown in FIG. 1B) and a check valve 192 for selectively inflating and deflating cuff 134.
In operation, cuff 134 is deflated, and the mask portion is then inserted through the patient's mouth into the patient's pharynx. The device is preferably positioned so that distal end 138 of mask portion 130 rests against the patient's normally closed esophagus and so that the open end 140 (shown in FIG. 1C) of mask portion 130 is aligned with the entryway of the patient's trachea (i.e., the patient's glottic opening). After the mask portion is so positioned, the cuff is inflated and forms a seal around the patient's glottic opening and thus establishes a sealed airway extending from a proximal end 114 of airway tube 110 to the patient's trachea.
For convenience of exposition, the term “fully inserted configuration” shall be used herein to refer to a laryngeal mask airway device that has been inserted into a patient and has the following characteristics: (1) the distal end of the mask portion is pressed against the patient's normally closed esophageal sphincter; (2) the cuff is inflated and forms a seal around the patient's glottic opening; and (3) the airway tube extends from a proximal end located outside the patient's mouth to a distal portion that is coupled to the mask portion, the tube extending through the patient's mouth and the patient's natural upper airway so that the device provides a sealed airway extending from the tube's proximal end to the patient's lungs.
FIG. 2 shows a laryngeal mask airway device 100 in the fully inserted configuration. As shown, the distal end of the mask portion 130 is pressed against the patient's esophageal sphincter 210. Also, the open end of the mask portion forms a seal around the glottic opening 212 thereby enabling the device 100 to provide fluid communication with the trachea 214.
Although prior art disposable laryngeal mask airway devices have performed well, there remains a need for providing improved devices. In particular, there remains a need for providing a disposable laryngeal mask airway device that more reliably remains stably in the fully inserted configuration once the device has been inserted into a patient.